HESI Dosage Calculations Practice Exam

HESI Dosage Calculations Practice Exam A client with cardiogenic shock weighs 220 lb and is receiving dopamine at the rate of 3 mcg/kg/minute. The solution strength available is dopamine 400 mg in 250 ml of D5W. The ...

HESI Dosage Calculations Practice Exam A client with cardiogenic shock weighs 220 lb and is receiving dopamine at the rate of 3 mcg/kg/minute. The solution strength available is dopamine 400 mg in 250 ml of D5W. The nurse should set the infusion pump to deliver how many ml/hour? (Enter numeric value only. If rounding is required, round to the nearest tenth.) Ans- 11.3 First, convert pounds to kg, 220 lb : X = 2.2 lb : 1 kg = 100 kg. Next, calculate the dosage per minute, 3 mcg/kg/min x 100 kg = 300 mcg/min. Convert mcg/min to mcg/hour, 300 mcg/min x 60 min=18,000 mcg/hour. Convert mcg/hr to mg/hour, 18,000 mcg/hr = 18.0 mg/hour. Calculate the rate, 400 mg : 250 ml = 18 mg : X ml 400X = 4500 X = 11.25 = 11.3 ml. So, 18 mg/11.3 ml should be infused at 11.3 ml/hour. A client with hypertension who weighs 72.4 kg is receiving an infusion of nitroprusside (Nipride) 50 mg in D5W 250 ml at 75 ml/hour. How many mcg/kg/minute is the client receiving? (Enter numeric value only. If rounding is required, round to the nearest tenth.) Ans- 3.5 Calculate the mg/hour infusing, 50 mg : 250 ml = X : 75 ml 250X = 3750 and X = 15 mg/hour. Next, convert mg/hr to mcg/hour, 15 mg/hour = 1 mg / 1000 mcg = 15,000 mcg/hour, then divide by 60 min = 250 mcg/minute. Lastly, 250 mcg/72.4 kg/min = 3.45 = 3.5 mcg/kg/minute. A client who weighs 70 kg is receiving a dopamine solution of 800 mg/500 ml normal saline at 5 ml/hour. How many mcg/kg/minute is the client receiving? (Enter numeric value only. If rounding is required, round to the nearest tenth.) Ans- 1.9 To change ml/hour to mcg/kg/minute, use the formula: desired rate (5 ml/hour) / volume available (500 ml) x dose available (800 mg) = 8 mg/hour. Next, convert milligrams/hour to mcg/kg/minute: mg (8) x 1000 / kg (70) / 60 minutes = 1.904 = 1.9 mcg/kg/minute. A client is receiving an IV solution of sodium chloride 0.9% (Normal Saline) 250 ml with amiodarone (Cordarone) 1 gram at 17 ml/hour. How many mg/minute of amiodarone is infusing? (Enter numeric value only. If rounding is required, round to the nearest tenth.) Ans- Convert grams to mg, 1 gram equals 1,000 mg. Using ratio and proportion - 1,000 mg : 250 ml :: X mg : 1ml 250X= 1,000 so X = 4 mg/ml is the solution concentration of amiodarone. The infusion rate (ml/hour) x concentration (mg/ml) divided by 60 minutes/hour 17 ml/hour x 4 mg/ml = 68/60 = 1.13 = 1.1 mg/minute. A client who weighs 176 pounds is receiving an IV infusion with esmolol hydrochloride (Brevibloc) at 48 ml/hour. The IV solution is labeled with the concentration of Brevibloc 10 mg/ml. How many mcg/kg/minute is the client receiving? (Enter numeric value only.) Ans- 100 Convert pounds to kg by dividing 176 pounds by 2.2 pounds = 80 kg. Convert the IV concentration from mg to mcg. 1 mg : 1000 mcg :: 10 mg : 10,000 mcg. Infusion rate (48 ml/hour) x concentration (10,000 mcg/ml) divided by 60 minutes/hour x 80 kg = 48 x 10,000 divided by 60 x 80 = 480,000 / 4800 = 100 mcg/kg/minute. The nurse is preparing the change-of-shift report for a client who has a 265 ml secondary infusion that was started 2 hours ago at a rate of 85 ml/hour via an infusion pump. The nurse should report that how many ml remain to be infused by the on-coming nurse? (Enter numeric value only.) Ans- 95 85 ml x 2 hours = 170 ml has infused. 265 ml (total amount to be infused) - 170 ml (amount infused) = 95 ml remain to be infused. A male client receives a prescription for ondansetron hydrochloride (Zofran) 4 mg IV to prevent postoperative nausea after an inguinal hernia repair. The medication is available in 2 mg/ml. How many ml should the nurse administer? (Enter numeric value only.) Ans- 2 Use ratio and proportion, 4 mg : X ml = 2 mg : 1 ml 2X = 4 X = 2 The nurse is preparing to administer Hepatitis B Vaccine, Recombinant (Energix-B) 5 mcg IM to a schoolaged child. The vaccine is labeled, 10 mcg/ml. How many ml should the nurse administer? (Enter numeric value only. If rounding is required, round to the nearest tenth). Ans- 1 or 0.5 Use ratio and proportion, 5 mcg : X ml :: 10 mcg : 1ml 10X = 5 X = 0.5 ml A client's daily PO prescription for aripiprazole (Abilify) is increased from 15 mg to 30 mg. The medication is available in 15 mg tablets, and the client already received one tablet today. How many additional tablets should the nurse administer so the client receives the total newly prescribed dose for the day? (Enter numeric value only.) Ans- 1 30 mg (total dose) - 15 mg (dose already administered) = 15 mg that still needs to be administered. Using the Desired/Have formula: 15 mg/15 mg = 1 tablet At the end of the shift, the nurse is recording the fluid balance for a client receiving a continuous gastrostomy tube (GT) feeding. Based on the client's records, how many ml should the nurse record for the total fluid balance (intake - output) for the shift that started at 0700 and ended at 1900? (Enter numeric value only.) (Click on each image asset for additional information.) Ans- 695 The tube feeding is administered at 75 ml/hour for 11 hours (0700 - 1800) and then turned off for one hour because the residual is greater than 200 ml. 11 hours x 75 ml/hr = 825 ml. Three doses of 20 ml of medication are administered, with 10 ml of water used to flush the GT before and after each dose. 20 ml x 3 doses = 60 ml; 10 ml (flush) x 2 x 3 doses = 60 ml; so 825 ml + 60 ml + 60 ml = 945 ml. 250 ml of residual is removed and not replaced. 945 ml - 250 ml = 695 ml total fluid balance (Intake - output). The nurse is administering a 250 milliliter (ml) intravenous solution to be infused over 2 hours. How many ml/hour should the nurse program the infusion pump? (Enter numeric value only.) Ans- 125 250 ml : 2 hours = X ml : 1 hour 250 = 2X X = 250 divided by 2 = 125 ml/hr The nurse is preparing to administer 0.25 mg of bumetanide (Bumex) IV. The medication is available in a vial labeled 1 mg/4 ml. How many ml of medication should the nurse administer? (Enter numeric value only.) Ans- 1 Using the Desired/Have x Volume formula: Desired = 0.25 mg Have = 1 mg Volume = 4 ml 0.25 mg/1 mg x 4 ml = 1 ml A client with hypertension receives a prescription for carteolol (Cartel) 7.5 mg PO daily. The drug is available in 2.5 mg tablets. How many tablets should the nurse administer? (Enter numeric value only.) Ans- 3 Using D/H: 7.5 mg / 2.5 mg = 3 tablets The healthcare provider prescribes trimethoprim-sulfamethoxazole (Bactrim-DS Oral Suspension) 120 mg BID for a child with bronchitis. The Bactrim bottle is labeled 200 mg/5ml. How many ml should the nurse administer at each dose? (Enter numeric value only.) Ans- 3 Using the formula D/H x Q, 120/200 x 5 = 3 ml A 180-pound adult male is admitted to the Emergency Center after receiving thermal burns to 60 percent of his body. Using the Parkland formula of 4 ml/kg/24 hours, the client should receive how many ml of fluid during the first 24 hours? (Enter numeric value only. If rounding is required, round to the nearest whole number.) Ans- 19632 Using the Parkland formula, the client's fluid requirements for the first 24 hours after injury: 4 ml lactated Ringer's solution x Body weight (in kilograms) x Percent burn. Convert 180 pounds to kg = 180 / 2.2 = 81.8 kg 4 ml x 81.8 kg x 60 = 19632 ml over the first 24 hours. The healthcare provider prescribes acetazolamide (Diamox) 600 mg/m2/day divided into 3 doses. The nurse calculates the child's body surface area (BSA) as 0.7 m2. How many mg should the child receive per dose? (Enter numeric value only.) Ans- 140 Using the child's BSA, 0.7 m2, calculate the mg/dose, 600 mg x 0.7 m2 = 420 mg/day/3 doses = 140 mg/dose A loading dose of acetylcysteine (Mucomyst) 8 grams, which is available as a 20% solution (200 mg acetylcysteine per ml) is prescribed by nasogastric tube for a client with acetaminophen toxicity. How many ml of diluent should be added to the medication to obtain a 1:4 concentration? (Enter numeric value only. If rounding is required, round to the nearest whole number.) Ans- 120 8 grams = 8,000 mg prescribed dose. Using the formula, D/H x Q, 8,000 mg / 200 mg x 1 ml = 40 ml of the 20% solution. Dilute the 40 ml to a 1:4 concentration for administration using ratio and proportion, 1 : 4 solution :: 40 ml : X X= 160 ml total volume to administer. Subtract total volume of 160 ml - 40 ml of 20% concentration = 120 ml diluent is added to obtain a 1:4 concentration. A child who weighs 55 pounds receives a prescription for atovaquone with proguanil (Malarone Pediatric) 125 mg/50 mg PO daily. A drug reference states that children 11 to 20 kg should receive 1 pediatric tablet daily; 21 to 30 kg should receive 2 pediatric tablets daily; 31 to 40 kg should receive 3 pediatric tablets daily; and greater than 40 kg should receive 1 adult tablet daily with food. The drug is available as atovaquone 62.5 mg/proguanil 25 mg pediatric tablets. How many tablets should the nurse administer? Ans- 2 Calculate each drug component dose, using the formula, D/H 125 mg / 62.5 mg (atovaquone) = 2 combined with 50 mg / 25 mg (proguanil) = 2. The child should receive 2 tablets. A client receives a prescription for azithromycin (Zithromax) 500 mg PO x 3 days. Azithromycin is available as 250 mg scored tablets. How many tablets should the nurse administer per dose? (Enter numeric value only. Ans- 2 Using the formula, D/H 500 mg/250 mg = 2 tablets A child who is scheduled for a kidney transplant receives a prescription for basiliximab (Simulect) 20 mg IV 2 hours prior to surgery. The medication is available in a 20 mg vial that is reconstituted by adding 5 ml sterile water for injection, and administered in a 50 ml bag of normal saline over 30 minutes. The nurse should program the infusion pump to deliver how many ml/hour? (Enter numeric value only. Ans110 After reconstituting the medication vial, the nurse adds the 5 ml of medication to the 50 ml of sterile water to result in a 55 ml volume to infuse in 30 minutes. Using the formula, Volume/Time = 55 ml / 0.5 hours = 110 ml/hour A client with a gastrostomy tube (GT) receives a prescription for Osmolite® 1/2 strength enteral formula at 80 ml/hour. To prepare a 4 hour solution, the nurse should dilute the full-strength formula with how many ml of water? (Enter numeric value only.) Ans- 160 Determine the total volume needed at 80 ml/hour x 4 hours = 320 ml. Use the formula, Desired strength/strength on Hand x Volume = 50/100 x 320 = 160 ml of Osmolite® enteral formula, which must be diluted to half strength. Or use ratio and proportion, Desired strength (1/2 = 1 part : 2 parts) :: Volume of full strength : Total Desire volume 1 : 2 :: X : 320 ml 2X = 320, and X = 160 ml of Osmolite® enteral formula, full strength 320 ml total volume - 160 ml of full-strength formula = 160 ml of water to create 1/2 strength or 50% concentration. The nurse notes that a client is receiving an oxytocin (Pitocin) infusion via a pump that is programmed to deliver 30 ml/hour. The available solution is Ringer's Lactated 1,000 ml with Pitocin 20 units. How many milliunits/minute is the client receiving? (Enter numeric value only.) Ans- 10 Convert units to milliunits, 20 x 1,000 = 20,000 units. Using D/H x Q = 30 ml/hour X/20,000 units x 1,000 ml = 30 ml/hour (60 minutes) X/20 =30/60, reduce X/2 = 1/2, and 2X = 20, so X = 10 milliunits/minute OR 20/1,000 = 0.02 1000 : 0.02 :: 30 : X = 0.6 :: 1,000X X = 600 and 600/60 = 10 milliunits/minute. A client is receiving Heparin Sodium 25,000 Units in 5% Dextrose Injection 500 ml IV at 1,000 unit/hour per protocol for acute coronary syndrome (ACS). The client's partial thromboplastin time (PTT) is 76 seconds. Based on the ACS protocol, the infusion should be decreased by 100 units/hour for a PTT between 71 to 80 seconds. The nurse should program the pump to deliver how many ml/hour? (Enter numeric value only.) Ans- 18 Adjust the infusion to 900 units/hour (1,000 units/hour minus 100 units/hour per protocol). Using the formula, D/H x Q, 900 units/1 hour divided by 25,000 units x 500 ml = 90/5= 18 ml/hour. The healthcare provider prescribes oxytocin (Pitocin) 0.5 milliunits/minute for a client in labor. One liter Ringer's Lactate with 10 units of oxytocin (Pitocin) is infusing. The nurse should program the infusion pump at how many ml/hour? (Enter numeric value only.) Ans- 3 Using the formula, D/H x Q, 0.5 milliunits / 10,000 milliunits x 1000 ml = 0.05 ml/minute. Multiply by 60 minutes = 3 ml/hour. Docusate sodium (Colace) 0.3 grams is prescribed for a client who has frequent constipation. Each capsule contains 100 mg. How many capsules should the nurse administer? Ans- 3 Using the known equivalent, 1 gram = 1000 mg, the nurse should first convert the dose to the same unit of measurement, which is 0.3 gram = 300 milligram. Using the formula, Desired / Available x 1 capsule = 300/100 x 1 = 3 capsules. A client who has a sinus infection is receiving a prescription for amoxicillin/clavulanate potassium (Augmentin) 500 mg PO q8 hours. The available form is 250 mg amoxicillin/125mg clavulanate tablets. How many tablets should the nurse administer for each dose? (Enter numeric value only.) Ans- 2 Using Desired/Available formula: 500 mg/250 mg x 1